Chelsea have fined goalkeeper Kepa Arrizabalaga one week's wages following his refusal to be substituted in the League Cup final defeat by Manchester City.
Arrizabalaga appeared to be injured as he prevented City's Sergio Aguero from scoring in the closing moments of extra time on Sunday, and manager Maurizio Sarri ordered his substitution before Chelsea went on to lose the Wembley showpiece match 4-3 on penalties.
But with the change already displayed to the stadium by the fourth official, and Chelsea's reserve keeper Willy Caballero ready to come on, Kepa insisted he was fit to carry on and face the penalty shootout - to Sarri's anger.
The Italian coach said after the match, which finished 0-0, there had been a "big misunderstanding" because he thought Arrizabalaga had cramp.
On Tuesday (NZ time), Arrizabalaga said he had apologised to Sarri, his teammates and the fans, while Chelsea fined him for his actions.
"Although there was a misunderstanding, on reflection, I made a big mistake with how I handled the situation," Kepa said.
"I wanted to take the time today to apologise fully and in person to the coach, to Willy, my teammates and to the club. I have done this and now I want to offer the same apology to the fans.
Sarri said after the match he would discuss the matter with Arrizabalaga, who became the world's most expensive goalkeeper when he joined Chelsea for 80 million euros ($NZ132m) last year.
"It was a good conversation. There was a misunderstanding yesterday but he realises he made a big mistake in the way he reacted," Sarri said.
"For me, this matter is now closed.
"The team performance as a whole was extremely positive and it is a shame to see how this incident has overshadowed our efforts."